about aromatic chemistry the meteorological effect Ringcurrent Image Aromaticring current.png thumb right 250px A diagram of an aromaticringcurrent. B sub 0 sub is the applied magnetic field, the red arrow indicating its direction. The orange ring shows the direction of the ringcurrent, and the purple rings show the direction of the electromagnetic induction induced magnetic field. An aromaticringcurrent is an effect observed in aromaticity aromatic molecules such as benzene and naphthalene . If a magnetic field is directed perpendicular to the plane of the aromatic system, a ringcurrent is induced in the delocalized pi bond electrons of the aromaticring. ref The induced magnetic field ... non aromatic molecules, they respond much more strongly to the magnetic field. Aromaticring currents ... proton in cyclohexene . In contrast any proton inside the aromaticring experiences shielding ... 1.1 ppm. Hence a diamagnetic ringcurrent or diatropic ringcurrent is associated with aromaticity whereas a paratropic ringcurrent signals antiaromaticity. A similar effect is observed in three dimensional fullerene s in this case it is called a sphere current . ref Sphere Currents of Buckminsterfullerene ... aromaticity with respect to the observed ringcurrent. ref What is aromaticity? Paul von Ragu ... 13 sup 13 sup C and hydrogen atom sup 1 sup H atomic nucleus nuclei in aromatic molecules, ref Aromaticity and Ring Currents. Gomes, J. A. N. F. Mallion, R. B. Chem. Rev. Review 2001 101 5 1349 1384. DOI 10.1021 cr990323h ref as well as in any organic or inorganic aromatic molecule. The effect helps .... In benzene, the ring protons experience deshielding because the induced magnetic field has ..., No. 12, pp. 1843 1846, 2005 DOI 10.1002 anie.200462348 PMID 15706578 ref Image Benzene ring currents.png thumb center 610px Magnetically induced probability current density vectors in benzene C sub ... the C sub 6 sub ring. Relative aromaticity align right class wikitable colspan 2 align center Selected ... more details
About an atmospheric effect the effect in nuclear magnetic resonance Chemical shift Factors causing chemical shifts A ring current is an electric current carried by charged particles trapped in a planet s magnetosphere . It is caused by the longitudinal drift of energetic 10&ndash 200 k electron volt eV particles. Earth s ring current File Currents.jpg thumb right 300px Schematic view of the different current systems which shape the Earth s magnetosphere . Earth s ring current is responsible for shielding the lower latitudes of the Earth from magnetospheric electric fields. It therefore has a large effect on the electrodynamics of geomagnetic storm s. The ring current system consists of a band, at a distance of 3 to 5 Earth radius R sub E sub , ref cite book title Introduction to Geomagnetically Trapped Radiation author Martin Walt year 1994 ref which lies in the celestial sphere equatorial plane and circulates clockwise around the Earth when viewed from the north . The particles of this region produce a magnetic field in opposition to the Earth s magnetic field and so an Earthly observer would observe a decrease in the magnetic field in this area. The ring current energy is mainly carried around by the ions, most of which are protons. However, one also sees alpha particles in the ring current, a type of ion that is plentiful in the solar wind. In addition, a certain percentage are O sup sup oxygen ions, similar to those in the ionosphere of Earth, though much more energetic. This mixture of ions suggests that ring current particles probably come from more than one source. The ring current and geomagnetic storms During a geomagnetic storm , the number of particles in the ring current will increase. As a result there is a decrease in the effects of Earth s magnetic field geomagnetic field . See also Van Allen radiation belt Magnetosphere References references cite journal doi 10.1023 B SPAC.0000007516.10433.ad title Ring Current Energy Input and Decay journal Space S ... more details
. Examples of non basic nitrogen containing aromatic rings are pyrrole and indole . The basic aromatic rings purine s and pyrimidine s are nucleobases found in DNA and RNA . See also Simple aromaticring DEFAULTSORT Basic AromaticRing Category Nitrogen heterocycles ar ur ... atom. Basic aromatic compounds get Protonation protonated and form aromatic cation s e.g. pyridinium under acid ic conditions. Typical examples of basic aromatic rings are pyridine or quinoline . Several ... aromatic rings the lone pair of electron s of the nitrogen atom is delocalized and contributes to the aromatic ... more details
. Heterocyclic aromatic rings The nitrogen N containing aromatic rings can be separated into basic aromaticring s that are easily protonation protonated , and form aromatic cation s and salts e.g., pyridinium , and non basic aromatic rings. In the basic aromatic rings , the lone pair of electron s is not part of the aromatic system and extends in the plane of the ring. This lone pair is responsible ... hydrocarbons PAH References reflist 2 DEFAULTSORT Simple AromaticRing Category Simple aromatic rings ...Simple aromatic rings , also known as simple arenes or simple aromatics , are aromatic organic compound s that consist only of a conjugated system conjugated planar ring system with delocalized electron delocalized pi electron clouds. Many simple aromatic rings have trivial names. They are usually found ... simple aromatic compounds are benzene , indole , and cyclotetradecaheptaene . ref name Clayden1st ... pages isbn 3527307206 ref Simple aromatic rings can be heterocyclic if they contain non carbon ring atoms, for example, oxygen , nitrogen , or sulfur . They can be monocyclic as in benzene, bicyclic as in naphthalene , or polycyclic as in anthracene . Simple monocyclic aromatic rings are usually five membered rings like pyrrole or six membered rings like pyridine . Fused aromatic rings consist ... 5 cellspacing 0 style margin 1em colspan 3 align center Table of simple aromatic rings WARNING ... the nitrogen atom is not connected to a hydrogen atom. Examples of basic aromatic rings are pyridine ... and contributes to the aromatic pi electron system. In these compounds, the nitrogen atom is connected to a hydrogen atom. Examples of non basic nitrogen containing aromatic rings are pyrrole and indole . In the oxygen and sulfur containing aromatic rings, one of the electron pairs of the heteroatoms contributes to the aromatic system similar to the non basic nitrogen containing rings , whereas the second lone pair extends in the plane of the ring similar to the basic nitrogen containing ... more details
Aromaticring hydroxylating dioxygenases ARHD incorporate two atoms of dioxygen O sub 2 sub into their substrates in the dihydroxylation reaction. The product is substituted cis 1,2 dihydroxycyclohexadiene, which is subsequently converted to substituted benzene glycol by a cis diol dehydrogenase. A large family of multicomponent mononuclear non heme iron oxygenases has been identified. Components of bacterial aromaticring dioxygenases constitute two different functional classes hydroxylase components and electron transfer components. Hydroxylase components are either sub n sub or sub n sub oligomers. Two prosthetic groups, a Rieske protein Rieske type Fe sub 2 sub S sub 2 sub center and a mononuclear iron, are associated with the subunit in the sub n sub type enzymes. Electron transfer components are composed of flavoprotein NADH ferredoxin oxidoreductase and Rieske type Fe sub 2 sub S sub 2 sub ferredoxin. In benzoate and toluate 1,2 dioxygenase systems, a single protein containing reductase and Rieske type ferredoxin domains transfers the electrons from NADH to the hydroxylase component. In the phthalate 4,5 dioxygenase system, phthalate dioxygenase reductase PDR has the same function. PDR is a single protein comprising FMN binding reductase and plant type ferredoxin domains. Thus, the electron transfer in ARHD systems can be summarised as ul border 0 width 60 cellpadding 3 cellspacing 1 center NADH center center center bgcolor yellow center reductase br FAD or FMN ... of the bacterial aromaticring hydroxylating dioxygenases journal Adv. Microb. Physiol. year ... from Rhodococcus sp. strain RHA1 InterPro IPR001663 InterPro entry for Bacterial ring hydroxylating dioxygenase, alpha subunit DEFAULTSORT AromaticRing Hydroxylating Dioxygenases Category Metalloproteins ..., E., Parales, R.E., Gibson, D.T., Eklund, H. and Ramaswamy, S. title Structure of an aromaticring hydroxylating dioxygenase &ndash naphthalene 1,2 dioxygenase journal Structure year 1998 volume ... more details
Infobox musical artist name Eddy Current Suppression Ring image Eddy Current Suppression Ring.jpg caption Eddy Current Suppression Ring, Golden Plains Festival landscape Yes background group or band genre ... plant stating he had to fix the eddy current suppression ring a copper ring around a transformer ... 09 27 accessdate 2008 06 12 title Interview, Eddy Current Suppression Ring ref Their first year ... booked to open the Meredith Music Festival in 2005. ref name ECSRgiglist File Eddy Current Suppression Ring 2.jpg thumb right 180px Lead singer Brendan Suppression, Golden Plains Festival March 2007 In 2006, Eddy Current Suppression Ring released their first full length recording, an eponymous album released to critical acclaim ref cite web publisher PBS FM title Feature CD Eddy Current Suppression Ring accessdate 2008 06 12 year 2006 url http www.pbsfm.org.au Documents.asp?ID 3845&Title Eddy Current Suppression Ring Eddy Current Suppression Ring Dead link date October 2010 bot H3llBot ... Eddy Current Suppression Ring date 2006 11 22 accessdate 2008 06 15 Dead link date October 2010 bot ... date 2009 03 20 accessdate 2009 03 20 title Eddy Current Suppression Ring takes out 30k music ... Eddy Current Suppression Ring Ready to roll url http www.abc.net.au triplej homeandhosed blog s2760939.htm ... current members Brendan Suppression vocals br Eddy Current guitar, keyboards br Rob Solid bass br Danny Current drums ref cite web publisher Spin magazine date November 2008 title Eddy Current Suppression Ring url http spin cdnsrc.texterity.com spin 200811 ?pg 50&pm 1 ref Eddy Current Suppression Ring is a Melbourne based Australian rock music rock group which rose to prominence in 2008. Biography ... 2008 05 29 1211654174608.html title Ring of Fire publisher The Age, Melbourne date 2008 05 30 accessdate ... triplej events ausmusicmonth 06 next crop eddy current supression ring.htm ref Reference has ..., Victoria Prahran, Vic isbn 978 1 74066 955 9 ref Discography Albums Eddy Current Suppression ... more details
Unreferenced date December 2009 An aromatic amine is an amine with an aromaticity aromatic substituent that is nitrogen N hydrogen H sub 2 sub , nitrogen N hydrogen H or nitrogen group s attached to an aromatic hydrocarbon , whose structure usually contains one or more benzene ring s. Aniline is the simplest example. Aromatic amines, when protonated, usually have lower pKa s are more acidic than their non aromatic analogs. This is due to the delocalization of the lone pair of electrons from the nitrogen into the ring. align center class wikitable colspan 6 align left style background ccccff Representative anilines Aromatic amine CAS number Properties Uses Aniline Image Aniline 2D skeletal.png 50px Aniline 62 53 3 O Toluidine o Toluidine Image O toluidinePIC.svg 100px o toluidine 95 53 4 2,4,6 Trimethylaniline Image TrimethylanilinePIC.svg 100px 88 05 1 O Anisidine Anisidine Image 2 Anisidine.png 75px Anisidine 90 04 0 3 Trifluoromethylaniline Image 3 trifluoromethylanilinePIC.svg 100px 3 trifluoromethylaniline 98 16 8 Intermediate for herbicides, metabolite N Methylaniline N Methylaniline Image N methylaniline.png 60px N methylaniline 100 61 8 See also Aromatic hydrocarbons DEFAULTSORT Aromatic Amine Category Aromatic amines it Ammine aromatiche hu Arom s aminok ja pl Aminy aromatyczne pt Amina arom tica sk Aromatick am n zh ... more details
Aromatic rice is one of the Oryza sativa Classification major types of rice ref cite web url http www.ers.usda.gov briefing Rice SpecialArticle USricemarket.pdf title The U.S. Rice Export Market publisher United States Department of Agriculture USDA date Nov 2000 br There are four types of rice traded globally indica, japonica rice japonica , aromatic, and glutinous rice glutinous . ref , it is a medium to long grained rice . It is known for its nut fruit nut like aroma and taste , which is caused by the chemical compound 2 acetyl 1 pyrroline . ref cite web url http www.springerlink.com content m53xn058318q4858 title Enhanced resistance to two stem borers in an aromatic rice containing a synthetic cryIA b gene ref Varieties of aromatic rice include basmati , Jasmine rice jasmine , Texmati, Wehani , and wild pecan rice. When cooked, the grains have a light and fluffy texture. References reflist Varieties of rice Category Varieties of rice ja food stub ... more details
Aromatic sulfonation is an organic reaction in which a hydrogen atom on an aromatic hydrocarbon arene is replaced by a sulfonic acid functional group in an electrophilic aromatic substitution . ref JerryMarch . ref File Benzene sulfonation overview.png center 500px Sulfonation of Benzene to benzene sulfonic acid Mechanism Sulfur trioxide is the electrophile in this electrophilic aromatic substitution generated from concentrated sulfuric acid or fuming sulfuric acid when heated. With benzene as substrate the reaction product is benzenesulfonic acid . Image Chem Mech SO3FormationWH2SO4.png generation of sulfur trioxide from sulfuric acid In contrast to aromatic nitration and other electrophilic aromatic substitutions this reaction is Reversible reaction reversible . Sulfonation takes place in concentrated acidic conditions and desulfonation is the mode of action in a dilute hot aqueous acid. It is very useful in protection group protecting the aromatic system because of this reversibility. Piria reaction A classic named reaction is the Piria reaction R. Piria , 1851 in which nitrobenzene is reacted with a metal bisulfite forming an aminosulfonic acid as a result of combined nitro group reduction and sulfonation. ref Piria, Ann. 78 31 1851 . ref ref THE PIRIA REACTION. I. THE OVER ALL REACTION W. H. Hunter, Murray M. Sprung J. Am. Chem. Soc. , 1931, 53 4 , pp 1432 1443 DOI 10.1021 ja01355a037 . ref File Piria reaction.png 400px center The Piria Reaction Tyrer sulfonation process In the Tyrer sulfonation process 1917 , ref US patent 1,210,725 ref at some time of technological importance, benzene vapor is led through a vessel containing 90 sulfuric acid the temperature of which is increased from 100 to 180 C. Water and benzene are continuously removed in a condenser and the benzene ..., Leipzig, 1985, p. 511, ISBN 3 342 00280 8. ref Application Aromatic sulfonic acids are intermediates ... Electrophilic halogenation Nitration References Reflist DEFAULTSORT Aromatic Sulfonation Category ... more details
Wiktionary currentCurrent may refer to toc right Ongoing events The present Current affairs disambiguation Current events Science and mathematics Current fluid , the flow of a liquid or a gas Air current , a flow of air Current ocean , a current in the ocean Rip current , type of ocean currentCurrent stream , currents in rivers and streams Current mathematics , geometrical current in differential topology Conserved current , a concept in physics and mathematics that satisfies the continuity equation Current density , a mathematical concept unifying electric current, fluid current, and others Electric current , a flow of electric charge through a medium Alternating current Direct current Business IBM Current , an early personal information management program Media Current album Current album , an album by Heatwave Current film Current film , a 2009 film Current newspaper Current newspaper , an American trade journal Current Publishing , an American publishing company Current TV , a cable television network owned by Al Gore Currents periodical Currents periodical , an international trade law journal Currents TV series Currents TV series , a Catholic news magazine television show in U.S. 89.3 The Current, public radio station KCMP licensed to Northfield, Minnesota The Current song The Current song , a song by the Blue Man Group People Jeff Current , lead singer for Against All Will Ships USS Current ARS 22 See also Currant disambiguation disambig ar cs Proud de Courant el es Corriente fr Courant gl Corrente it Courant disambigua he nl Courant pl Current ru simple Current sk Pr d tr Ak m ... more details
The Current can refer to the following The Current Columbia University journal The Current journal , Columbia University s student journal of politics, culture and Jewish affairs. The Current newspaper The Current newspaper , the student newspaper of the University of Missouri St. Louis The Current NSU The Current newspaper , the student newspaper of the Nova Southeastern University The Current radio program , a current affairs radio program on CBC Radio One The Current song The Current song , a song by the Blue Man Group featuring Gavin Rossdale KCMP , a Minnesota Public Radio station known as The Current disambig ... more details
Image L phenylalanine skeletal.png thumb phenylalanine Image L tryptophan skeletal.png thumb tryptophan Image L tyrosine skeletal.png thumb tyrosine Image Histidin Histidine.svg thumb histidine Image Thyroxine 2D skeletal.png thumb thyroxine Aromatic amino acids are amino acids that include an Aromaticity aromatic ring. Examples include Among 20 standard amino acids phenylalanine , tryptophan , histidine and tyrosine Others thyroxine See also Aromatic L amino acid decarboxylase Phenylalanine , histidine , and tryptophan are essential amino acids for animals. Since they are not synthesized in the human body, they must be derived from the diet. Tyrosine is semi essential it can be synthesized, but only from phenylalanine. A lack of the enzyme phenylalanine hydroxylase used in tyrosine synthesis causes phenylketonuria . All plants and micro organisms must synthesize their aromatic amino acids in order to make proteins, unlike animals which obtain them through their diet. Because of the energy intensive nature of amino acid biosynthesis, animals have lost these costly metabolic pathways, since they can obtain aromatic amino acids by ingesting other organisms. Herbicides and antibiotics take advantage of this by inhibiting enzymes involved in aromatic acid synthesis, thereby rendering them toxic to plants and micro organisms but not animals. External links MeshName Aromatic Amino Acids MetabolismMap Category Amino acids Category Aromatic amino acids biochemistry stub zh ... more details
is slow because it is in a higher energy state than the aromatic reactant. The loss of the chloride is fast, because the ring becomes aromatic again. Nucleophilic aromatic substitution reactions Some ...image Aromatic nucleophilic substitution.svg right 300px Aromatic nucleophilic substitution A nucleophilic aromatic substitution is a substitution reaction in organic chemistry in which the nucleophile displaces a good leaving group , such as a halide , on an aromaticring . There are 6 nucleophilic substitution mechanisms encountered with aromatic systems the S sub N sub Ar addition elimination mechanism image SNAr mechanism.svg 300px SNAr mechanism the aromatic SN1 mechanism encountered with diazonium salt s image Aromatic SN1 mechanism.svg 300px Aromatic SN1mechanism the benzyne mechanism image ... N sub Ar mechanism, where electron withdrawing group s activate the ring towards nucleophilic attack, for example if there are nitro functional group s positioned aromatic ortho substituent ortho or aromatic para substituent para to the halide leaving group. S sub N sub Ar reaction ... bond is in the plane of the ring as the carbon atom is trigonal. To attack from the back, the nucleophile would have to appear inside the benzene ring and invert the carbon atom in an absurd way. This reaction ... sub N sub 1 doesn t occur. The following is the reaction mechanism of a nucleophilic aromatic substitution ... 800px Nucleophilic aromatic substitution In this sequence the carbons are numbered clockwise from ... electrons of the carbanion become bonded to the aromatic pi system which allows the ipso ... version of this reaction type. Nucleophilic aromatic substitution is not limited to arenes, however ... when substituted in the aromatic ortho position or aromatic para position because then the negative ... Aromatic Substitution Freddy Tjosaas and Anne Fiksdahl Molecules journal Molecules 2006 , 11, 130 ... Nucleophilic aromatic substitution at pyridine Asymmetric nucleophilic aromatic substitution With prochiral ... more details
The Ring may refer to tocright Film The Ring 1927 film The Ring 1927 film , a film by Alfred Hitchcock The Ring 1952 film The Ring 1952 film , a film by Kurt Neumann The Rings , a 1985 horror film by Honarmand, aka Zangha The Ring 1996 film The Ring 1996 film , a film by Armand Mastroianni Ring film Ring film , a 1998 Japanese horror film by Hideo Nakata, aka Ringu or The Ring The Ring 2002 film The Ring 2002 film , a horror film by Gore Verbinski, a remake of the Japanese film Literature The Ring , a book by Daniel Keys Moran The Ring novel The Ring novel , by Danielle Steel The Ring , a children s book by John Updike The Ring magazine The Ring magazine , a boxing periodical The Ring poem The Ring poem , a poem by Heinrich Wittenwiler Television The Ring Angel The Ring Angel , a 2000 episode of Angel The Ring Chuck The Ring Chuck , a fictional spy organization in Chuck The Ring South Park The Ring South Park , a 2009 episode of South Park The Ring Yes, Dear The Ring Yes, Dear , an episode of Yes, Dear Other uses N rburgring or the Ring, a German racetrack The Ring rock formation , a rock formation in Bulgaria The Ring Terror s Realm , a 2000 video game Vaginal ring or the Ring, a hormonal contraceptive device The Ring album The Ring album , an album by Terri Hendrix See also One Ring , a fictional ring of power in J. R. R. Tolkien s Middle earth The Ring of the Nibelung or Der Ring des Nibelungen , a cycle of operas by Richard Wagner Ring disambiguation disambiguation da Ringen de The Ring fr The Ring id The Ring hu The Ring no The Ring pl The Ring ru sv The Ring ... more details
The term RingRing may refer to RingRing album RingRing album , an album by Bj rn & Benny, Agnetha & Anni Frid who would later become ABBA RingRing song RingRing song , a song by Bj rn & Benny, Agnetha & Anni Frid RingRing, a song by singer songwriter Mika singer Mika s which is a bonus track on his debut album Life in Cartoon Motion RingRing, a 14 year old girl in the Pucca TV series, see List of characters in Pucca disambig cs RingRing fr RingRing ko RingRing nl RingRing ... more details
wiktionary ringRing may refer to Ring jewellery , a decorative ornament worn on fingers, toes, or around the arm or neck tocright Arts and entertainment The Rings , a 1985 horror film by Honarmand Ring film Ring film , a 1998 horror film by Hideo Nakata Rings short film Rings short film , a 2005 horror film by Jonathan Liebesman Ring video game Ring video game , a 1999 computer game Ring Suzuki novel Ring Suzuki novel , a 1991 Japanese horror novel by Koji Suzuki Ring Stephen Baxter novel Ring Stephen Baxter novel , a 1994 science fiction novel by Stephen Baxter Music Ring song Ring song , by Japanese duo B z Ring The Connells album Ring The Connells album , 1993 Ring Miliyah Kato album Ring Miliyah Kato album Ring Gary Burton album Ring Gary Burton album , 1974 Ring band , a 1980s British band Der Ring des Nibelungen , the cycle of four epic operas by Richard Wagner Rings song Rings song , a 1971 song by Tompall & the Glaser Brothers Science and technology Ring computer security , a layer of protection in computer systems Ring data structure , also known as ring buffer or circular buffer Ring geometric , or annulus, a circular shape Ring mathematics , an algebraic structure Ring of sets A sound in the ear s , which may be a symptom of tinnitus Ring chemistry , a cyclic molecule Planetary ring , matter orbiting a planet RING finger domain , a protein structural domain People Alexander Ring born 1991 , Finnish footballer Nick Ring born 1979 , Canadian martial artist Joey Ring 1758 1800 , English cricketer Places Ireland Ring, County Waterford , a village United States Ring, Wisconsin , an unincorporated community Sports Championship ringRing boxing Ring wrestling Ring name Ring of Honor disambiguation Rings gymnastics , a gymnastics apparatus and its associated event RINGS, a martial arts organization also known as Fighting Network Rings Other uses Ring diacritic , as in m l See also Category Rings Category Rings Brass ring Claddagh ring Class ring Cock ring Engagement ... more details
and deactivating towards the aromaticring. Activating substituents or activating group s stabilize the cationic intermediate formed during the substitution by donating electrons into the ring system, by either inductive effect or resonance effect s. Examples of activated aromatic rings are toluene , aniline and phenol . The extra electron density delivered into the ring by the substituent is not equally divided over the entire ring, but is concentrated on atoms 2, 4 and 6 the ortho and para ... the reaction rate . They do so by withdrawing electron density from the aromaticring, though the positions ... for this reaction, the electron rich aromaticring, which in the simplest case is benzene , attacks ...Electrophilic aromatic substitution is an organic reaction in which an atom that is attached to an aromaticringaromatic system usually hydrogen is replaced by an electrophile . Some of the most important electrophilic aromatic substitutions are aromatic nitration , aromatic halogenation , aromatic ... Nitration of Benzene Aromatic sulfonation of benzene with fuming sulfuric acid gives benzenesulfonic acid. Image BenzeneSulfonation.png Sulfonation of Benzene Aromatic halogenation of benzene with bromine ... aromatic substitution are affected by the substituents already attached to the benzene ring. In terms of regioselectivity, some groups promote substitution at the ortho or para positions ... aromatic substitution might thus be hard to predict, and it is usually only established ... or, least unreactive are the meta ones atoms 3 and 5 . Examples of deactivated aromatic rings are nitrobenzene , benzaldehyde and trifluoromethylbenzene . The deactivation of the aromatic system ... nitration, on the activated toluene ring, can be done at room temperature and with dilute acid, the second one, on the deactivated nitrotoluene ring, already needs prolonged heating and more concentrated ... pair of electrons, their ability to do this is rather limited. Thus they only weakly activate the ring ... more details
Orphan date January 2011 Chlorinated polycyclic aromatic hydrocarbons ClPAH s are a group of compounds comprising polycyclic aromatic hydrocarbon s with two or more aromaticring s and one or more chlorine atoms attached to the ring system. ClPAHs can be divided into two groups chloro substituted PAHs, which have one or more hydrogen atoms substituted by a chlorine atom, and chloro added ClPAHs, which have two or more chlorine atoms added to the molecule. ref name Nilsson1993 Nilsson, U. L., Oestman, C. E. Chlorinated polycyclic aromatic hydrocarbons method of analysis and their occurrence in urban air. Environ. Sci. Technol. 1993 27 9 1826&ndash 1831. doi 10.1021 es00046a010 ref They are products ... Trends and Relationships of Particulate Chlorinated Polycyclic Aromatic Hydrocarbons and Their Parent ... water solubility. ref Cerniglia, C. E. Biodegradation of polycyclic aromatic hydrocarbons. Biodegradation ..., M. Chlorinated Polycyclic Aromatic Hydrocarbons in the Atmosphere Seasonal Levels, Gas ... ref Sources of ClPAHs Chlorinated polycyclic aromatic hydrocarbons are generated by combustion ... Aromatic Hydrocarbons. The Scientific World. 2007 7 372&ndash 380. PMID 17334629 ref ClPAHs ... Aromatic Hydrocarbons in Environmental Samples from an Electronic Waste Recycling Facility and a Chemical ..., D. Analysis and structure prediction of chlorinated polycyclic aromatic hydrocarbons released ... and Profiles of Chlorinated and Brominated Polycyclic Aromatic Hydrocarbons in Waste Incinerators ... Kitazawa2006 The relative potency of three ring ClPAHs was found to increase with increasing degree ...., Ohura, T., Kannan K. Relative Potencies of Individual Chlorinated and Brominated Polycyclic Aromatic ... polycyclic aromatic hydrocarbons can exert their toxic effects is via the function of the aryl hydrocarbon ... T., Makino M. Occurrence, Profiles, and Photostabilities of Chlorinated Polycyclic Aromatic Hydrocarbons ... Chlorinated Polycyclic Aromatic Hydrocarbon Category Organochlorides Category Incineration Category ... more details
aromatic hydrocarbons PAH s , also known as poly aromatic hydrocarbons or polynuclear aromatic hydrocarbons , are potent atmospheric pollutants that consist of fused aromatic simple aromaticring .... The name comes from benzene , an aromatic hydrocarbon with a single, six membered ring. These can ... clearly are aromatic compounds, the degree of aromaticity can be different for each ring segment. According ... sextet. Therefore in this molecule the outer rings are firmly aromatic while its central ring is less ...Image Polycyclic Aromatic Hydrocarbons.png thumb An illustration of typical polycyclic aromatic hydrocarbons .... C. title The Chemistry and Analysis of the Large Polycyclic Aromatic Hydrocarbons year 2000 doi 10.1080 10406630701268255 isbn 0471363545 publisher Wiley location New York journal Polycyclic Aromatic ... title Polycyclic Aromatic Hydrocarbons Occurrence in foods, dietary exposure and health effects publisher ... last Larsson first B. K. year 1983 title Polycyclic aromatic hydrocarbons in grilled food journal J ... toxfaqs tf.asp?id 121&tid 25 title Polycyclic Aromatic Hydrocarbons PAHs year 1996 publisher Agency ... motif is extended to large 2D sheets. Occurrence and pollution Polycyclic aromatic hydrocarbons ... conversion of natural product molecules, such as steroids, to aromatic hydrocarbons. They are also ... Aromatic Hydrocarbons place London publisher Imperial College Press isbn 1 86094 417 5 ref ... prenatal pah exposure child behavior problems title Prenatal Polycyclic Aromatic Hydrocarbon PAH Exposure ... first4 Julia year 2012 title Prenatal Polycyclic Aromatic Hydrocarbon PAH Exposure and Child ... Moss, IUPAC nomenclature for fused ring systems , are phenanthrene and anthracene , which both contain three fused aromatic rings. Smaller molecules, such as benzene , are not PAHs. PAHs may contain four ... that do not contain a complete benzene ring. The set of alternant PAHs is closely related to a set ... by conjoining regular hexagon s of identical size. PAHs containing up to six fused aromatic rings ... more details
With This Ring was a prime time panel show aired by the DuMont Television Network from January 21, 1951 to March 11, 1951. The show featured engagement engaged couples discussing marriage and marital problems. It was initially hosted by Bill Slater broadcaster Bill Slater , but the show quickly changed hosts to Martin Gabel , then left the air. ref http www.dumonthistory.tv a2.html DuMont historical website ref This show is not related in any way to a 15 minute television syndication syndicated program of the same name that aired weekly usually on Sundays on local stations throughout the U.S. for about 25 years beginning in the early 1970s. The latter program was a Roman Catholic produced show concerning the Church s doctrinal and moral positions on marriage and family life, and was produced at WJBK TV in Detroit . See also List of programs broadcast by the DuMont Television Network List of surviving DuMont Television Network broadcasts References reflist Bibliography David Weinstein, The Forgotten Network DuMont and the Birth of American Television Philadelphia Temple University Press , 2004 ISBN 1 59213 245 6 Alex McNeil, Total Television , Fourth edition New York Penguin Books , 1980 ISBN 0 14 024916 8 Tim Brooks and Earle Marsh, The Complete Directory to Prime Time Network TV Shows , Third edition New York Ballantine Books , 1964 ISBN 0 345 31864 1 External links http www.imdb.com title tt0331158 With This Ring at IMDB http www.dumonthistory.tv a2.html DuMont historical website Category DuMont Television Network shows Category 1950s American television series Category 1951 television series debuts Category 1951 television series endings Nonfiction tv prog stub ... more details
Orphan date December 2008 The Aromatic transition state theory assumes that the minimum energy transition state for a pericyclic process must be aromatic . For 4n 2 sysyems 2,6,10... H ckel s rule Huckel transition states are proposed where the molecule is flat. In 4n sysyems 4,8,12... M bius aromaticity Mobius transition states are proposed which involve a twist or require a node to be aromatic. References Unreferenced date June 2009 Category Physical organic chemistry chem stub ... more details
Radical nucleophilic aromatic substitution or S sub RN sub 1 in organic chemistry is a type of substitution reaction in which a certain substituent on an aromatic compound is replaced by a nucleophile through an intermediary free radical species Image Radical nucleophilic aromatic substitution overview.png 300px center Radical nucleophilic aromatic substitution overview The substituent X is a halide and nucleophiles can be sodium amide , an alkoxide or a carbon nucleophiles such as an enolate . ref Phenomenon of radical anion fragmentation in the course of aromatic SRN reactions Roberto A. Rossi Acc. Chem. Res. 1982 15 6 pp 164 170 DOI 10.1021 ar00078a001 . ref In contrast to regular nucleophilic aromatic substitution , deactivating group s on the arene are not required. ref Rossi, R. A. Pierini, A. B. Santiago, A. N. Org. React. 1999 , 54 , 1.doi http dx.doi.org 10.1002 0471264180.or054.01 10.1002 0471264180.or054.01 ref This reaction type was discovered in 1970 by Bunnett and Kim ref Evidence for a radical mechanism of aromatic nucleophilic substitution Joseph F. Bunnett and Jhong Kook Kim J. Am. Chem. Soc. 1970 92 25 pp 7463 7464. DOI 10.1021 ja00728a037 ref and the abbreviation ... mechanism Image Radical nucleophilic aromatic substitution Mechanism.png 400px center Radical nucleophilic aromatic substitution Mechanism In this radical substitution the aryl halide 1 accepts an electron ... in a new type of nucleophilic aromatic substitution was invoked when the product distribution was compared between a certain aromatic chloride and an aromatic iodide in reaction with potassium ... Image Radical nucleophilic aromatic substitution Bunnett 1970.png 400px center Radical nucleophilic aromatic substitution Bunnett 1970 It now resembles ipso substitution with 1a forming preferentially ... the opposite. ref Alkali metal promoted aromatic nucleophilic substitution Joseph F. Bunnett and Jhong ... See also Birch reduction Nucleophilic aromatic substitution Category Free radical reactions Category ... more details
enzyme Name aromatic amino acid transaminase EC number 2.6.1.57 CAS number 37332 38 0 IUBMB EC number 2 6 1 57 GO code 0008793 image width caption In enzymology , an aromatic amino acid transaminase EC number 2.6.1.57 is an enzyme that catalysis catalyzes the chemical reaction an aromatic amino acid 2 oxoglutarate math rightleftharpoons math an aromatic oxo acid L glutamate Thus, the two substrate biochemistry substrates of this enzyme are aromatic amino acid and 2 oxoglutarate , whereas its two product chemistry products are aromatic oxo acid and L glutamate . This enzyme belongs to the family of transferase s, specifically the transaminases , which transfer nitrogenous groups. The systematic name of this enzyme class is aromatic amino acid 2 oxoglutarate aminotransferase . Other names in common use include aromatic amino acid aminotransferase , aromatic aminotransferase , and ArAT . This enzyme participates in 6 metabolism metabolic pathways methionine metabolism , tyrosine metabolism , phenylalanine metabolism , phenylalanine, tyrosine and tryptophan biosynthesis , novobiocin biosynthesis , and alkaloid biosynthesis i . It employs one cofactor biochemistry cofactor , pyridoxal phosphate . Structural studies As of late 2007, 13 tertiary structure structures have been solved for this class of enzymes, with Protein Data Bank PDB accession codes PDB link 1AY4 , PDB link 1AY5 , PDB link 1AY8 , PDB link 2AY1 , PDB link 2AY2 , PDB link 2AY3 , PDB link 2AY4 , PDB link 2AY5 , PDB link 2AY6 , PDB link 2AY7 , PDB link 2AY8 , PDB link 2AY9 , and PDB link 3TAT . References reflist 1 cite journal author Mavrides C, Orr W date 1975 title Multispecific aspartate and aromatic amino acid aminotransferases in Escherichia coli journal J. Biol. Chem. volume 250 pages 4128&ndash 33 pmid 236311 issue 11 transferase stub Category EC 2.6.1 Category Pyridoxal phosphate enzymes Category Enzymes of known structure ... more details
Orphan date February 2009 Primary aromatic amines PAA are a group of compounds. They might be added to plastic s during production. In animal testing the PAAs have been shown to be related to cancer , and one form of PAA has been found in unacceptable high levels in kitchen utensils made of black nylon in China . External links Danish Institute for Food and Veterinary Research , http www.dfvf.dk Admin Public DWSDownload.aspx?File Files 2FFiler 2FF C3 B8devaresikkerhed 2FMaterialer og genstande 2FPAA from black nylon cooking utentils 2004.pdf An acute case of primary aromatic amines migrating from cooking utensils , Memorandum for the Danish Veterinary and Food Administration, 2004 October 12 Category Materials chemistry stub ... more details
enzyme Name aromatic hydroxylamine O acetyltransferase EC number 2.3.1.56 CAS number 52660 15 8 IUBMB EC number 2 3 1 56 GO code 0047188 image width caption In enzymology , an aromatic hydroxylamine O acetyltransferase EC number 2.3.1.56 is an enzyme that catalysis catalyzes the chemical reaction N hydroxy 4 acetylaminobiphenyl N hydroxy 4 aminobiphenyl math rightleftharpoons math N hydroxy 4 aminobiphenyl N acetoxy 4 aminobiphenyl Thus, the two substrate biochemistry substrates of this enzyme are N hydroxy 4 acetylaminobiphenyl and N hydroxy 4 aminobiphenyl , whereas its two product chemistry products are N hydroxy 4 aminobiphenyl and N acetoxy 4 aminobiphenyl . This enzyme belongs to the family of transferase s, specifically those acyltransferase s transferring groups other than aminoacyl groups. The systematic name of this enzyme class is N hydroxy 4 acetylaminobiphenyl N hydroxy 4 aminobiphenyl O acetyltransferase . Other names in common use include aromatic hydroxylamine acetyltransferase , arylhydroxamate acyltransferase , arylhydroxamate N,O acetyltransferase , arylhydroxamic acid N,O acetyltransferase , arylhydroxamic acyltransferase , N,O acetyltransferase , and N hydroxy 2 acetylaminofluorene N O acyltransferase . References reflist 1 cite journal author Bartsch H, Dworkin C, Miller EC, Miller JA date 1973 title Formation of electrophilic N acetoxyarylamines in cytosoles from rat mammary gland and other tissues by transacetylation from the carcinogen N hydroxy 4 acetylaminobiphenyl journal Biochim. Biophys. Acta. volume 304 pages 42&ndash 55 pmid 4699998 issue 1 transferase stub Category EC 2.3.1 Category Enzymes of unknown structure it Aromatic idrossilammina O acetiltransferasi ... more details
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